The present invention relates to a powder container applicable to an electrophotographic image forming apparatus for storing toner, or powdery coloring agent, and a device for discharging the toner from the powder container.
A toner container customarily used with a copier or similar electrophotographic apparatus is implemented as a cartridge, bottle or similar hard case. Generally, the toner container is collected from the user""s station by a manufacturer and recycled, reused or burned out. In this respect, the hard case has a problem that it is bulky and increases the collection cost.
A toner container whose volume can be reduced has been proposed in the past. However, this kind of toner container cannot stably replenish toner to a developing unit. Also proposed in the past is a toner container whose volume can be reduced only during transport. Even this toner container has a problem that when toner is transferred from the container to a hard bottle or a toner hopper, the toner is scattered around and contaminates the surrounding.
To stably replenish toner to a developing unit, there has been proposed a toner replenishing device that uses a toner container formed of resin, paper or similar flexible sheets and capable of being reduced in volume. The toner container for this application is made up of a deformable bag storing the toner and a box more rigid than the bag and accommodating the bag therein. In this bag-in-box type of toner container, the bag includes a tapered portion and a toner discharging portion including a tapered toner outlet. The tapered portion and toner outlet cause a minimum of toner to be left in the bag. The bag-in-box type of toner container, however, has a problem that when a shock or an impact acts on the container at the time of, e.g., shipment, the bag buckles around the tapered portion and tapered toner outlet due to, e.g., the weight of the toner. This, coupled with the fact that the portion of the bag around the toner outlet is narrow, prevents the toner from being smoothly delivered during operation or causes much toner to be left in the bag.
Moreover, the toner container for the toner replenishing device is usually held in an upright position with the toner outlet facing downward. This brings about another problem that the flexible bag is apt to fall down due to its own weight and stop up the toner outlet. In addition, when a certain amount of toner is delivered from the bag, the creases of the bag fallen down catch the toner and causes more toner to be left in the bag.
Technologies relating to the present invention are disclosed in, e.g., Japanese Patent Laid-Open Publication Nos. 6-274031, 9-22175, 11-119536 and 11-282236.
It is therefore a first object of the present invention to provide a powder container free from buckling and a powder discharging device using the same.
It is a second object of the present invention to provide a flexible powder container that falls down little even when used in an upright position, and a powder discharging device using the same.
It is a third object of the present invention to provide an image forming apparatus using the above powder container and powder discharging device.
In accordance with the present invention, a powder container for storing powder and allowing the powder to be discharged includes a discharging portion that includes a deformable bag and a tapered portion configured to discharge the powder. A buckle reducing device reduces, when the toner container is held in an upright position with the discharging portion facing downward and being fixed, the buckling of the tapered portion.
Also, in accordance with the present invention, a powder container includes a deformable bag storing powder, and a position maintaining device configured to maintain the position of the bag.
Further, in accordance with the present invention, in a powder discharging device for discharging coloring powder from a powder container via an outlet formed in the container, the powder container includes a deformable bag storing the coloring powder, a position maintaining device configured to maintain the position of the bag, and a mounting portion configured to removably mount the bag. A gas is fed into the bag in order to fluidize the coloring powder and cooperates with the position maintaining device to maintain the position of the bag.